Magnesium-aluminum alloy



Lemma May 11, 1926.

mm s r:

iss ess HERMAN IE. BAKKEN, OF NIAGARA FALLS, NEW YORK, ASSIGNOR 'IOAMERICAN MAG- NESIUM CORPORATION, OF NIAGARA FALLS, NEW YORK, ACORPORATION OF NEW YORK.

MAGNESIUM-ALUMINUM ALLOY.

No Drawing My invention relates to magnesium alloys and one ofthetobjects of the invention is to provide an alloy of this metal whichwill possess a greater resistance to corrosion 5 against theelementsthan that ordinarily exhibited by commercial magnesium or its alloys. I

Magnesium is one of the lightest of the hard metals. Thisproperty inconnection with a goodatensile strength makes it a highly desirablemetal where reduction in weight is of prime consideration, as in air andland vehicles. One deterrent to its wider use heretofore has been itsmarked tendency to corrosion even under normal atmospheric conditions; I

\Vith the object of overcoming this disadvantage, I have discovered thatthe tendency of this metal or'its alloys to corrode is best overcomewhen alloyed with manganese. A particular alloy that I have found to behighly resistant to corrosion is magnesium with 8% of aluminum and 1percent or less of m nganese. -The particular percentage of aluminumused is not a factor in so far as the corrosive properties of the alloyis concerned as other percentages of aluminum might be used with equalbeneficial results. The ratio of magnesium 0 and aluminum is determinedby other required physical properties of the alloy. \Vhile I have not atthis time determined the exact range in the amount of 'manga-' nese thatwill produce the necessary results, it is obvious that in order to keepthe spe cific gravity of the alloy as low as possible, the tendency willbe to add as little manganese as possible. Proportions from 0.2% to 1%ofmanganese have been found effective in increasing the resistance tocorrosion.

The alloy isprepared by first adding the 5 Application filed August 25,1920. Serial No..405,865.

1. An alloy, having a specific gravity approximating that of magnesium,comprising a major quantity of magnesium, a minor quantity of aluminum,and a quantity of manganese not widely different from one per cent, thequantity of aluminum being in excess of the quantity of manganese.

2. An alloy, having a specific gravity approximating that of magnesium,c0mprising a major quantity of magnesium, a minor quantity of aluminum,and from O.2L% .manganese, the quantity of aluminum being in excess ofthe quantity of manganese.

3. A ternary alloy composed of a main body of magnesium combined withabout 1 per cent or less of manganese, and aluminum in an amount greaterthan that of manganese but substantially less than that. of magnesium-4. An alloy composed of magnesium, 8% of aluminum and 1% or less ofmanganese.

5. The method of making amagnesiumaluminum-manganese alloy-whichconsists in first 'interfusmg the manganese and aluminum and adding thisalloy to the magnesium.

In testimony whereofI aflix my signature.

HERB/IAN E. BAKKEK.

